A notification popup widget.
This is the legacy notification widget. It was the default until Awesome v4.3 but is now being deprecated in favor of a more flexible widget.
The reason for this is/was that this widget is inflexible and mutate the state of the notification object in a way that hinder other notification widgets.
If no other notification widget is specified, Awesome fallback to this widget.
Use the naughty.notification.position property to control where the popup is located.